Expose uv_version() for libuv API compatibility (#491)

* Also renamed to have libuv_ namespace

Author: fantix

tests/test_libuv_api.py

@@ -0,0 +1,22 @@
+from uvloop import _testbase as tb
+from uvloop.loop import libuv_get_loop_t_ptr, libuv_get_version
+
+
+class Test_UV_libuv(tb.UVTestCase):
+    def test_libuv_get_loop_t_ptr(self):
+        loop = self.new_loop()
+        cap1 = libuv_get_loop_t_ptr(loop)
+        cap2 = libuv_get_loop_t_ptr(loop)
+        cap3 = libuv_get_loop_t_ptr(self.new_loop())
+
+        import pyximport
+
+        pyximport.install()
+
+        from tests import cython_helper
+
+        self.assertTrue(cython_helper.capsule_equals(cap1, cap2))
+        self.assertFalse(cython_helper.capsule_equals(cap1, cap3))
+
+    def test_libuv_get_version(self):
+        self.assertGreater(libuv_get_version(), 0)

tests/test_pointers.py

@@ -501,3 +501,5 @@ cdef extern from "uv.h" nogil:
                  const uv_process_options_t* options)
 
     int uv_process_kill(uv_process_t* handle, int signum)
+
+    unsigned int uv_version()

uvloop/includes/uv.pxd

@@ -3226,9 +3226,14 @@ cdef class Loop:
         except Exception as ex:
             self.call_soon_threadsafe(future.set_exception, ex)
 
-    # Expose pointer for integration with other C-extensions
-    def get_uv_loop_t_ptr(self):
-        return PyCapsule_New(<void *>self.uvloop, NULL, NULL)
+
+# Expose pointer for integration with other C-extensions
+def libuv_get_loop_t_ptr(loop):
+    return PyCapsule_New(<void *>(<Loop>loop).uvloop, NULL, NULL)
+
+
+def libuv_get_version():
+    return uv.uv_version()
 
 
 cdef void __loop_alloc_buffer(uv.uv_handle_t* uvhandle,